RE: 100G DWDM FEC standard
Hi Mikael,
From a standards perspective keep in mind that http://www.stupi.se/Standards/100G-long-haul4.pdf is not approved - but we are working hard on it. OTOH having a reference implementation at hand, is an accelerator that helps a lot.
Let me also add some color to your email as the current interoperability situation in WDM is quite funny. Sometimes transceivers of the same vendor can't talk to each other, as they are based on a different generation of ASICs and therefore FEC implementations. In other words, vendors typically have more than only one secret sauce they cook with, and different sauces do not blend well :-) . Perhaps transport folks are already too used to deal with such kind of issues that no one laments anymore. On the other hand perhaps, the networking industry is already so used to Ethernet where interoperability is a no-brainer, that it is difficult to imagine what it means to deal with a technology that prevents multi-vendor interop. To confirm your final point: Interoperability is on the top of the shopping lists for the networking industry. Gert email : ggrammel@juniper.net --------------------------------------- Date: Fri, 5 Jun 2015 17:53:58 +0200 (CEST) From: Mikael Abrahamsson <swmike@swm.pp.se> To: nanog@nanog.org Subject: 100G DWDM FEC standard Message-ID: <alpine.DEB.2.02.1506051741330.9487@uplift.swm.pp.se> Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII Hi, I just watched the "evolution of ethernet speeds" presentation from NANOG meeting. There was a statement that there was "vendor secret sauce" in the 100G DWDM space. Yes, that is true, but: http://www.stupi.se/Standards/100G-long-haul4.pdf There actually is a standard for 100G DWDM that has support from multiple router vendors. When you buy new gear, make sure your vendors support the above standard, so we can connect our routers over longer distances between vendors, without needing transponders. We in the Deutsche Telecom Terastream project have Huawei, Cisco, Juniper and ALU routers that natively (DWDM colored interfaces in the routers) talk directly to each other over 1500 km amplified DWDM system (no transponders), and we can also talk from these routers interfaces to Cisco and ALU transponders if we want to. https://jeffloughridge.wordpress.com/2013/10/16/peter-lothbergs-terastream-p... if you want to know more about the project. Next time you purchase 100G DWDM equipment, make sure you buy equipment that follows this standard to be certain that it interoperates to combat vendor "secret sauce". -- Mikael Abrahamsson email: swmike@swm.pp.se
From a standards perspective keep in mind that http://www.stupi.se/Standards/100G-long-haul4.pdf is not approved - but we are working hard on it. OTOH having a reference implementation at hand, is an accelerator that helps a lot.
There is a whole industry that do not want it to be plug and play... (The ones that do not make routers or switches..)
Let me also add some color to your email as the current interoperability situation in WDM is quite funny. Sometimes transceivers of the same vendor can't talk to each other, as they are based on a different generation of ASICs and therefore FEC implementations. In other words, vendors typically have more than only one secret sauce they cook with, and different sauces do not blend well :-) . Perhaps transport folks are already too used to deal with such kind of issues that no one laments anymore. On the other hand perhaps, the networking industry is already so used to Ethernet where interopera bility is a no-brainer, that it is difficult to imagine what it means to deal with a technology that prevents multi-vendor interop.
All vendors have secret souce for 100G SD-FEC, and just the fact that you can wire the wire the differential encoding eight ways.. That;s why we settled on a HD-FEC that can be inside the DSP-Asic or inline after it. All to us known DSP implementations supports this with more, less or no extra logic. And the logic is free and fully documented.
To confirm your final point: Interoperability is on the top of the shopping lists for the networking industry.
Amen! -P
participants (2)
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Gert Grammel
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Peter Lothberg